US2956537A - Fire detection and alarm systems - Google Patents

Description

Oct. 18, 1960 P. w. SMITH FIRE DETECTION AND ALARM SY STEMS 2 Sheets-Sheet 1 Filed May 21, 1959 I II II I fiw, ww/

Y I V mww ATTORN EY Oct. 18, 1960 P. w. SMITH 2,956,537

FIRE DETECTION AND ALARM SYSTEMS Filed May 21, 1959 2 Sheets-Sheet 2 \a Q Q I a a \u X TN INVENT BY I -7M W ATTORN EY FIRE DETECTION AND ALARM SYSTEMS Philip W. Smith, 7525 Limekiln Pike, Philadelphia, Pa.

Filed May 21, 1959, Ser. No. 814,744

3 Claims. (Cl. 116-103) The object of this invention is to devise a novel fire detection and alarm system for the protection of lives and property in homes, shops and commercial establishments which will eliminate maintenance costs and which is not dependent on electrical wiring or an electrical source of power.

A further object of the invention is to devise a system which will be automatically controlled by the forces against which protection is desired.

A further object is to devise a novel heat detecting mechanism.

Other objects and advantages of the system will hereinafter appear in the detailed description and the appended claims. a

For the purpose of illustrating the invention, I have shown in the accompanying drawings a preferred embodiment of it which I have found in practice to give satisfactory and reliable results. It is, however, to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized, and the invention is not limited, except by the scope of the appended claims, to the exact arrangement and organization of these instrumentalities as herein set forth.

Figure 1 is a front elevation of a fire detection and alarm system, embodying my invention.

Figure 2 is a side elevation, viewed from the right hand side of Figure 1.

Figure 3 is a side elevation, viewed from the left hand side of Figure 1.

Figure 4 is a schematic plan view of a building showing heat detecting devices arranged in different rooms of the building.

Figure 5 is an enlarged sectional elevation of a valve controlling the passage of water to actuate the alarm.

Figure 6 is an enlarged front elevation of an air release device.

Figure 7 is a top plan view of a heat detecting unit.

Figure 8 is a front view of a perforated plate for a heat detecting unit.

Figure 9 is a section on line 99 of Figure 7.

Similar numerals of reference indicate corresponding parts.

Referring to the drawings:

The alarm unit A panel 1 has an alarm 2 mounted on it and shown for purpose of illustration as a bell, the striking power for sound being a bell clapper 3 pivotally mounted at one end of a shaft 4 of a water powered motor 5. The motor 5 is mounted in a housing 6 into which water under pressure is introduced through an inlet pipe 7 leading from a source of water supply, and having a jet 8 through which water is projected against the blades of the motor to revolve the motor. The motor housing 6 has a discharge pipe 9 and an air vent 10.

The passage of water to the jet 8 is controlled by a valve mechanism 11 having an inlet and an outlet and a valve seat 12 therebetween. A spring 13 normally retains States Patent a valve 14 against said seat, and the seat is mounted on a threaded lug 15 secured to the body portion of the valve mechanism. The plug is apertured to communicate with the outlet of the valve mechanism. A valve plunger 16 is longitudinally movable in the plug and extends into a recess in the valve 14.

The trigger mechanism A spring housing 18 contains a spring 19 which con-. tacts a trigger 20 and tends to move it downwardly. The trigger bears against the upper end of the valve plunger 16, is offset, and is provided with a handle 23 for manually resetting the trigger. The tension of the spring is adjusted by a cap 21 threaded on the housing 18. The trigger 20 rides on the periphery of a trigger control member in the form of a plate 24 pivotally mounted at 25 at its lower end on a subpanel 26 mounted on the panel 1. The trigger plate has a raised shoulder 27 with which the trigger contacts when the valve 14 is in its closed position. The top periphery of the plate at one side of the shoulder inclines downwardly so that when the trigger plate is moved in a clockwise direction the valve 14 will open.

A bellows 28 has one end pivotally connected with the lower end of the plate at one side of the pivot and is mounted on the subpanel 26. A counter spring 29 is connected to the opposite side of the pivot point of the trigger plate and at its opposite end is connected to an adjusting screw 30 on a bracket 31 mounted on the subpanel 26.

The heat detecting system The bellows 28 is connected by a system of tubing 32 provided with heat detecting units 33 located in the rooms of the building which is to be protected.

An air valve 35 is provided for filling the system with compressed air, and an air gauge 36 indicates the maintained pressure in the system.

A heat detecting unit 33 consists of a metallic casing 37 in which are assembled and housed the components of a heat detecting unit. A metallic bellows 38 is filled with a heat expandable gas and hermetically sealed. A spring 39 governs the travel of the bellows under pressure when heat is applied and maintains the normal position of the bellows in its normally contracted position.

An air release valve arrangement 40 is adjustably mounted on the casing 37 by a lock nut 41 to obtain a selected distance between the bellows 38 and a valve stem 42 of a lower valve, thereby providing adjustment for various temperature settings. The air release valves are of conventional construction such as for example a tire valve, and I employ two of such valves in tandem arranged one above the other to protect against valve failure of a single valve.

Insulating gaskets 43 isolate the bellows and its spring from the casing, thus permitting more rapid sensitivity to temperature changes. A coupling 44 connects a heat detecting unit to the tubing 32.

The water housing 6 is made in sections sealed by an inner sealing ring 46 secured in position by fastening devices 47.

In the operation, air is pumped into the system through air valve 36 until sufficient pressure is built up in the system to expand the bellows 28 and impart a counterclockwise movement to the trigger plate 24 with trigger 20 riding on the periphery of the plate. Reset handle 23 is raised to allow the trigger plate to move to its normal position shown in Figure 1. The tension of counter spring 29 is adjusted to a pressure where if all air is discharged from the system the bellows 28 will return to its contracted condition and counter spring 29 will exert pressure against the trigger plate to cause a clockwise movement of the plate whereupon the spring 19 will force the trigger downwardly and the plunger 16 will open the water valve to actuate the water motor and the alarm.

The system becomes operational upon filling the system with air, turning on the water supply valve and setting the trigger to its normal operating position. Thus, when heat is applied to any heat detecting unit 33 heated expandable gas in its bellows 38 will cause pressure to build up and expand the bellows against its spring 39 which in turn controls the travel stroke in relation to pressure. Upon further expansion of the bellows, the bellows head contacts the stem of the lower air release valve thereby opening both valves and causing air to discharge from the system. Such air discharge activates the mechanical triggering mechanism to sound an alarm.

It will be apparent from the foregoing that the spring 39 opposing the expansion of the bellows 38 provides lost motion means in the travel stroke of the bellows to prevent the release of the valve before the room temperature is reached at ,which the system actuates the valve and alarm.

Having thus described my invention, what I claim as new and desire to secure by Letters Patents is:

1. In a fire detecting and alarm system, a line of tubing containing air under a determined pressure, valve mecha-.

nism in said tubing controlling release of air from said tubing, an alarm, actuating means for said alarm operatively connected with said tubing and actuated by release of air from said tubing, and a heat detector controlling said valve mechanism, comprising a hermetically sealed bellows containing an expandable gas, and a lost motion means between said valve mechanism and bellows preventing the bellows from actuating the valve mechanism to release air from said tubing until the bellows has been subjected to a predetermined degree of heat.

2. In a fire detecting and alarm system, a line of tubing containing air under a determined pressure, valve mechanism in said tubing controlling release of air from said tubing, an alarm, actuating means for said alarm operatively connected with said tubing and actuated by release of air from said tubing, and a heat detector controlling said valve mechanism, comprising a hermetically sealed bellows containing an expandable gas, and a spring engaging said bellows between said valve mechanism and bellows preventing the bellows from actuating the valve mechanism to release air from said tubing until the bellows has been subjected to a predetermined degree of heat.

3. The construction defined in claim 1, wherein the valve mechanism has a plurality of valves arranged in tandem.

References Cited in the file of this patent UNITED. STATES PATENTS 2,521,469 Marks Sept. 5, 1950 2,721,992 Evans Oct. 25, 1955 2,889,798 Smith June 9, 1959

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